US Patent 6931125 Telephone equipment compatible, twelve button alphanumeric keypad

A keypad for entering a complete set of alphanumeric characters (including symbols) into telephonic equipment comprises a housing containing a telephone set compatible array of manually operated actuator elements, each actuator element selectably coding for four or more alphanumeric characters upon a single actuation of the element. The manually operated actuator elements each comprises a push button assembly and a switch assembly. The switch assembly further comprises two or three switches. In a two-way switch assembly, the push button assembly is manually operable to selectably close either switch individually and both switches together. In a three-way switch, the push button assembly is manually operable to selectably close any one of the three switches individually. The push button assembly includes a push button cover that has an upper surface that serves as a user interface, which is configured to facilitate a user's operation of the actuator elements (keys) to selectively enter discrete alphanumeric selections into the keypad.